1. Point-Slope Form Thursday, November 4, 2010

2. Formula y – y 1 = m(x – x 1 ) – y 1 is the y-coordinate – m is the slope – x 1 is the x-coordinate

3. Graphing Using Point-Slope Form Graph the equation y – 5 = ½ (x – 2) – The equation shows that the line passes through (2, 5) with slope of ½. – Start at (2, 5). Using the slope, go up 1 unit and right 2 units to (4,6). Draw a line through the two points.

4. Graph the equation y – 5 = -⅔(x +2)

5. Writing an Equation in Point-Slope Form Write the equation of the line with the slope -3 that passes through the points (-1, 7). – Use the point-slope form y – y 1 = m(x – x 1 ) – Substitute (-1, 7) for (x 1, y 1 ) and -3 for m. y – 7 = -3(x –(-1)) y – 7 = -3(x + 1)

6. Write an equation of the line with slope ⅔ that passes through (10,-8). y + 8 = ⅔(x – 10)

7. Write an equation of the line with slope 6 that passes through (3,-4). y + 4 = 6(x – 3)

8. Write an equation of the line with slope 0 that passes through (-5, 2). y - 2 = 0(x + 5) y – 2 = x + 5

9. Closure What is the formula for point-slope? – y – y 1 = m(x – x 1 ) What does each piece represent? – y 1 is the y-coordinate – m is the slope – x 1 is the x-coordinate